Abstract: A zoom lens in which a distance between adjacent lens units changes during zooming includes in order from an object side to an image side a first lens unit fixed during zooming and having positive refractive power, three or more moving lens units movable during zooming, and a final lens unit fixed during zooming and having positive refractive power. At least part of the first lens unit moves during focusing. At least one of a moving lens unit closest to an image plane among the three or more moving lens units and the final lens unit includes a first lens having positive refractive power. A predetermined condition is satisfied.

Abstract: A zoom lens includes, in order from an object side to an image side, a lens unit closest to the object side and having a positive refractive power, an intermediate unit including at least three lens units and an aperture stop, and a lens unit closest to the image side and having a positive refractive power. A distance between each pair of adjacent lens units changes in zooming. The lens unit closest to the object side is configured not to move for zooming, and the at least three lens units and the aperture stop are configured to move in zooming. The lens unit closest to the image side includes a first positive lens. A predetermined condition is satisfied.

Abstract: A reduction optical system disposed on an image side of a main optical system, a composite focal length of the main optical system and the reduction optical system being shorter than a focal length of the main optical system, includes a first lens element disposed closest to an object side and having a positive refractive power, a second lens element disposed closest to an image side and having a positive refractive power, and a positive lens and a negative lens disposed between the first lens element and the second lens element.

Abstract: A reduction optical system (Gr) disposed on an image side of a main optical system is configured such that a composite focal length of the main optical system and the reduction optical system is shorter than a focal length of the main optical system. The reduction optical system has a positive refractive power, and includes a plurality of positive lenses and a plurality of negative lenses. The reduction optical system satisfies inequalities with respect to a lateral magnification of the reduction optical system disposed on the image side of the main optical system, a focal length of the reduction optical system, a focal length of a positive lens Gp1 included in the plurality of positive lenses, and a refractive index of the positive lens Gp1.

Abstract: A zoom lens includes, in order from an object side to an image side, a first lens unit that has a positive refractive power and does not move for zooming, a second lens unit that has a negative refractive power and moves in zooming, at least two lens units that move in zooming, and a final lens unit that has a positive refractive power, is disposed closest to the image side, and does not move for zooming. The first lens unit includes, in order from the object side to the image side, a first sub-lens unit that has a negative refractive power and does not move for focusing, a second sub-lens unit that has a negative refractive power and moves for focusing, and a third sub-lens unit having a positive refractive power. A distance between the second sub-lens unit and the third sub-lens unit changes for focusing. Predetermined inequalities are satisfied.

Abstract: A zoom lens includes, in order from an object side to an image side, a lens unit closest to the object side and having a positive refractive power, an intermediate unit including at least three lens units and an aperture stop, and a lens unit closest to the image side and having a positive refractive power. A distance between each pair of adjacent lens units changes in zooming. The lens unit closest to the object side is configured not to move for zooming, and the at least three lens units and the aperture stop are configured to move in zooming. The lens unit closest to the image side includes a first positive lens. A predetermined condition is satisfied.

Abstract: Provided is a zoom lens consisting of, in order from an object side to an image side: a positive front lens unit configured not to move for zooming; a plurality of magnification-varying lens units including two magnification-varying lens units having negative refractive powers configured to move for zooming; and a positive rear lens unit configured not to move for zooming, in which a focal length of the front lens unit, a focal length of a magnification-varying lens unit having a negative refractive power and arranged closest to the object side in the plurality of magnification-varying lens units, a focal length of a magnification-varying lens unit having a negative refractive power and arranged closest to the image side in the plurality of magnification-varying lens units, and a focal length of the rear lens unit are suitably set.

Abstract: A reduction optical system disposed on an image side of a main optical system, a composite focal length of the main optical system and the reduction optical system being shorter than a focal length of the main optical system, includes a first lens element disposed closest to an object side and having a positive refractive power, a second lens element disposed closest to an image side and having a positive refractive power, and a positive lens and a negative lens disposed between the first lens element and the second lens element.

Abstract: A reduction optical system (Gr) disposed on an image side of a main optical system is configured such that a composite focal length of the main optical system and the reduction optical system is shorter than a focal length of the main optical system. The reduction optical system has a positive refractive power, and includes a plurality of positive lenses and a plurality of negative lenses. The reduction optical system satisfies inequalities with respect to a lateral magnification of the reduction optical system disposed on the image side of the main optical system, a focal length of the reduction optical system, a focal length of a positive lens Gp1 included in the plurality of positive lenses, and a refractive index of the positive lens Gp1.

Abstract: A fixed focal length lens includes, in order from an object side, a first lens unit having a positive refractive power, a second lens unit having a positive refractive power and a third lens unit having a positive refractive power, the second lens unit and the third lens unit moving for focusing differently from each other to change a distance between each pair of adjacent lens units changes. The first lens unit includes, in order from the object side to the image side, a first lens having a negative refractive power and a second lens having a negative refractive power. A focal length of the fixed focal length lens in a case of focusing on an object at infinity, a focal length of the first lens unit, a focal length of the second lens unit and a focal length of the third lens unit are appropriately set.

Abstract: Provided is a zoom lens consisting of, in order from an object side to an image side: a positive front lens unit configured not to move for zooming; a plurality of magnification-varying lens units including two magnification-varying lens units having negative refractive powers configured to move for zooming; and a positive rear lens unit configured not to move for zooming, in which a focal length of the front lens unit, a focal length of a magnification-varying lens unit having a negative refractive power and arranged closest to the object side in the plurality of magnification-varying lens units, a focal length of a magnification-varying lens unit having a negative refractive power and arranged closest to the image side in the plurality of magnification-varying lens units, and a focal length of the rear lens unit are suitably set.

Abstract: A fixed focal length lens including, in order from an object side to an image side, a first lens unit having a positive refractive power, a second lens unit and a third lens unit, wherein the first lens unit does not move for focusing, at least the second lens unit moves for focusing, a distance between each pair of adjacent lens units changes for focusing, and the first lens unit includes two negative lenses disposed in succession from the object side, and wherein a focal length of the fixed focal length lens, a focal length of the first lens unit, and a combined focal length of the two negative lenses of the first lens unit are appropriately set.

Abstract: A fixed focal length lens includes, in order from an object side, a first lens unit having a positive refractive power, a second lens unit having a positive refractive power and a third lens unit having a positive refractive power, the second lens unit and the third lens unit moving for focusing differently from each other to change a distance between each pair of adjacent lens units changes. The first lens unit includes, in order from the object side to the image side, a first lens having a negative refractive power and a second lens having a negative refractive power. A focal length of the fixed focal length lens in a case of focusing on an object at infinity, a focal length of the first lens unit, a focal length of the second lens unit and a focal length of the third lens unit are appropriately set.

Abstract: A fixed focal length lens including, in order from an object side to an image side, a first lens unit having a positive refractive power, a second lens unit and a third lens unit, wherein the first lens unit does not move for focusing, at least the second lens unit moves for focusing, a distance between each pair of adjacent lens units changes for focusing, and the first lens unit includes two negative lenses disposed in succession from the object side, and wherein a focal length of the fixed focal length lens, a focal length of the first lens unit, and a combined focal length of the two negative lenses of the first lens unit are appropriately set.

Abstract: A zoom lens includes, in order from the object side to the image side, a positive first lens unit, a negative second lens unit, a positive third lens unit, and a positive fourth lens unit. The lens units move during zooming from the wide angle end to the telephoto end. The first lens unit consists of three or less lenses. The second lens unit consists of four or less lenses. The third lens unit consists of four or less lenses. The fourth lens unit consists of two or less lenses. The lateral magnification ?3w of the third lens unit at the wide angle end, the lateral magnification ?3t of the third lens unit at the telephoto end, the focal length f3 of the third lens unit, and the focal length ft of the entire system at the telephoto end are determined appropriately.

Abstract: A zoom lens includes, in order from an object side to an image side, a first lens unit having a positive refractive power, a second lens unit having a negative refractive power, an aperture stop, a third lens unit having a positive refractive power, and a rear lens group including at least one lens unit, the first lens unit is positioned closer to the object side at a telephoto end than at a wide-angle end, the third lens unit includes at least one positive lens, and a partial dispersion ratio ?gF3P of a material of one positive lens in the third lens unit, Abbe's number ?d3P, focal lengths fW and fT of a total system at the wide-angle end and the telephoto end respectively, a focal length f1 of the first lens unit, and a focal length f3 of the third lens unit are appropriately set.

Abstract: A zoom lens includes, in order from the object side to the image side, a positive first lens unit, a negative second lens unit, a positive third lens unit, and a positive fourth lens unit. The lens units move during zooming from the wide angle end to the telephoto end. The first lens unit consists of three or less lenses. The second lens unit consists of four or less lenses. The third lens unit consists of four or less lenses. The fourth lens unit consists of two or less lenses. The lateral magnification ?3w of the third lens unit at the wide angle end, the lateral magnification ?3t of the third lens unit at the telephoto end, the focal length f3 of the third lens unit, and the focal length ft of the entire system at the telephoto end are determined appropriately.

Abstract: A zoom lens includes, in order from an object side to an image side, a first lens unit having negative refractive power, a second lens unit having positive refractive power, and a third lens unit having positive refractive power. A distance between every adjacent ones of the first to third lens units varies during zooming. The second lens unit includes, in order from the object side to the image side, a positive lens and a cemented lens in which a positive lens and a negative lens are cemented. A focal length (f2) of the second lens unit, a focal length (fT) of the entire zoom lens at a telephoto end, and an average refractive index (Npave) of materials of the positive lenses included in the entire zoom lens are appropriately set.

Abstract: A zoom lens includes, in order from an object side to an image side, a first lens unit of a negative refractive power, a second lens unit of a positive refractive power, and a third lens unit of a positive refractive power, an interval between the first lens unit and the second lens unit and an interval between the second lens unit and the third lens unit being configured to change in zooming from a wide angle end to a telephoto end. The first lens unit includes, in order from the object side to the image side, a negative lens and a positive lens. The predetermined conditions are satisfied.

Abstract: A zoom lens includes, in order from an object side to an image side, a first lens unit having a positive refractive power, a second lens unit having a negative refractive power, an aperture stop, a third lens unit having a positive refractive power, and a rear lens group including at least one lens unit, the first lens unit is positioned closer to the object side at a telephoto end than at a wide-angle end, the third lens unit includes at least one positive lens, and a partial dispersion ratio ?gF3P of a material of one positive lens in the third lens unit, Abbe's number ?d3P, focal lengths fW and fT of a total system at the wide-angle end and the telephoto end respectively, a focal length f1 of the first lens unit, and a focal length f3 of the third lens unit are appropriately set.